Disk speed

I'm going to finally finish Xenogears. I just completed Sora no Kiseki SC so why not ride the long RPG train until the end of time? This save file is more than five years old, and I am just now getting past the point that I stopped playing when I got my NA copy so many years back: the tournament. Which I'm thinking was not very far.
But damn, even on the Vita (or especially on the Vita?) it's so slow. Every time I access the memory card it is a good few seconds before the game even response to button presses again. Every transition is a decent wait. And the camera likes to twist itself right behind walls and overpasses and all sorts of things. This is rough. Which feels weird since I've played a lot of 16-bit games over the past year and they don't feel nearly as rough. Which makes sense, but still feels bizarre.